Posted by Kenya on Thursday, February 19, 2009 at 9:15pm.
In January, gasoline cost $1.05 per gallon. In July, gasoline cost $1.20 per gallon. Find the percent of increase.
Would the answer for this question be 14.3?
And how do you do percent of decrease?
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The original cost of a computer is $900. If the price is decreased by 15%, what is the sale price?
I need help with this question(:
Thank you

Adv. Math  bobpursley, Thursday, February 19, 2009 at 9:18pm
percent (increase or decrease) is
Percent= (finalinitial)/initial * 100
fifteen percent of 900 is 130 dollars.
so the cost is 900130 dollars
price=(100percentdecrease)/100 * 900 
Adv. Math  Chopsticks, Thursday, February 19, 2009 at 9:20pm
bob, this looks kind of like exponential growth and exponential decay, is it? I was just wondering since we just started on exponential decay today.